Stabilizing and guide apparatus for lifter roof tanks



D. E. LARSON STABILIZING AND GUIDE APPARATUS FOR LIFTER ROOF TANKS Aug.2, W49.

3 Sheets-Sheet 1 Filed July 13, 1946 Aug. 2, 1949. D. E. LARSON2,477,629

STABILIZING AND GUIDE APPARATUS I FOR LIFTER ROOF TANKS Filed July 13,1946 5 Sheets-Sheet 2 Aug. 2, 1949. D. E. LARSON 2,477,629

- STABILIZING AND GUIDE APPARATUS FOR LIFTER ROOF TANKS Filed July 13,1946 3 Sheets-Sheet 5 V. i a

Patented Aug. 2, 1949 s'resrmzrno AND onion APrAngr s no mar na noonTANKS Donald E. Larson, Eureka, Calif., assignor to Chicago Bridge &iron Company, a corporation of Illinois Application July 13. 1946,Serial This invention relates to a lifter roof tank, and particularly toa stabilizing and guide apparatus for said tank.

Lifter roof tanks are used for the storage of gas and mixtures of liquidand gas. As the pressure within the tank is increased and decreased theroof rises and falls. The lifter roof is located over the shell of thetank, which constitutes the main storage portion, and flexible sealingmeans are provided between the shell and the roof. This sealin means isordinarily fabric impregnated with a flexible impervious solid such assynthetic rubber. It has been found necessary in tanks of this type thatstabilizing means be provided for maintaining the roof substantiallylevel at all times, even when subjected to unequal loads. It

is also advisable to provide guide means for pre venting rotation of theroof with its subsequent twisting of the flexible sealing member. Theusual relief valves and safety devices are also employed.

In the present invention improved stabilizing and guide means have beenprovided for maintaining the roof level at all times and for preventingrotation of the roof, These stabilizing and guide means may be used notonly on a dry seal roof wherein the sealing member is the previouslydescribed flexible sealing member, but may also be used on wet sealroofs wherein a liquid is used to seal the area between the roof and theshell. The invention broadly comprises a plurality of substantiallyparallel depending arms rotatably attached at their upper ends to theroof with each arm rotatably attached at its lower end to a movablemember located adjacent the shell of the tank, a guide member on thetank shell for guiding each of said movable members in a helical pathagainst the shell as the roof rises and falls, and guide means betweenthe roof and the shell for preventing rotation of the roof as it risesand falls. The guide members are all arranged at substantially the sameacute angle with respect to the horizontal and all extend in the samedirection around the shell.

The invention will be described as related to the embodiments shown inthe accompanying drawings. Of the drawings Fig. 1 is a fragmentary planview of a lifter roof tank embodying the invention with portions brokenaway for clarity of illustration; Fig. 2 is an elevation of said tankshowing the roof in its highest position; Fig. 3 is a vertical sectiontaken along line 3-3 of Fig. 2; Fig. 4 is a fragmentary elevationshowing the roof in its lowest position; Fig. 5 is an elevation of analternate embodiment of the invention showing 4 iliainis. (Cl. 48 -176)the roof in its highest position; and Fig. 6 is an elevation of saidalternate embodiment showing the roof in its lowest position.

The lifter ro'oi tank comprises a shell H}, a lifter roof ll thereover,a depending skirt i2 on the edge of the roof, and beyond the shell iii,and a flexible sealingmemb er l3 extending between the skirt i 2 and thetop of the shell I0.

Located around the tank and rotatably attached to the bottom of theskirt 12 are a plurality of equally spaced depending arms I 4. Each armit has its top attached to 'a downwardly extending mounting 15 on theinner end of a horizontal bracket is located' atthebottom of the skirt1?. The bottom end of'ea h arm" I4 is rotatably attached to ahorizbntalbar 'i'l extending inwardly toward'the shell. Around'tlieshell, but spaced therefrom, there is" located "a" structural member it!formed of pipe and "having theshape of a regular polygon. Eachhorizontal bar I! is attached to the structural member 18 at an apex ofthe polygon.

On the inner end of each bracket [6 there is located a roller I9 heldflat against the shell l0. On either side of each roller [9 there islocated a guide member 20 formed of angle iron attached to the shellalong one flange, with the other flanges of two of the guide membersextending toward each other. These guide members 20 are verticallyarranged and serve to prevent rotation of the roof as it rises andfalls.

At the inner end of each horizontal bar I! is located a second roller 21also held flat against the shell ll]. Each roller is provided with twosimilar guide members 22 also formed of pieces of angle iron attached tothe shell in. Each pair of guide members 22 are arranged atsubstantially 45 angles with respect to the horizontal and are shapedlike a section of a helix. All of these latter guide members have thesame angle and extend in the same direction around the shell.

The horizontal structural member it is formed straight lengths of pipecoupled together by coupling members 23 forming the apices of thepolygon. Each horizontal bar A? is attached to a coupling member 23. Thestructural memher is reinforced at each apex by a cross bar formed of apiece of angle iron. At its midpoint each cross bar 24 is adjacent theshell, and the bottom end of a depending arm M extends through thismidpoint. The bottom end 25 of each depending arm id is flattened, withthe flat"ened portion bein provided with a hole through which thehorizontal bar extends. The tOp end 2-? of each depending arm I4 is alsoflattened, and is provided with a hole through which a short rod 27extends. This short rod 21 is held by a mounting iii.

In the embodiment shown in Figs. 1 to 4 inclusive the tops of the lowerguide members 22 are substantially joined to the bottoms of the verticalguide members 23. There is provided a short bar 28 across the bottom ofeach pair of vertical guide members 20 to limit the upward movement ofthe roof H. In the embodiment shown in Figs. 5 and 6 each pair of slopedbottom guide members 22a is offset from the vertical guide members 26with the bottom guide members 22a being beneath the Vertical guidemembers 25.

As the roof rises and falls the vertical guide members 26 serve toprevent rotation of the roof. The sloped guide members 22 and 22acombined with the horizontal polygonal structural member is serve tomaintain the roof substantially horizontal at all times, and equalizethe load on the roof.

Having described my invention as related to the embodiments shown in theaccompanying drawings, it is my intention that the invention be notlimited by any of the details of description unless otherwise specified,but rather be construed broadly within its spirit and scope as set outin the accompanying claims.

I claim:

1. In a lifter roof tank comprising a shell and a movable roof thereoverhaving a downwardly extending skirt attached thereto and located beyondthe shell, stabilizing and guide means comprising inclined roller guidesattached below corresponding vertical roller guides, both roller guidesbeing attached to the outside of the shell, a plurality of rollersattached to the roof skirt and engaging the vertical guides, a pluralityof rollers 4 ngagin the inclined guides and attached to the apices of acommon horizontal structural member of polygonal shape extending aroundthe shell but spaced therefrom, and arms of equal length connected atone end to the roller attached to the roof skirt and connected at theother end to the rollers engaging the inclined guides at the apices ofsaid polygonal member, each of said arms being movable in a planesubstantially parallel to the shell wall.

2. The stabilizing and guide means of claim 1 wherein the top of eachinclined guide is substantially alined with the bottom of itscorresponding vertical guide.

3. The stabilizing and guide means of claim 1 wherein the top of eachinclined guide is offset to one side of and above the bottom of itscorresponding vertical guide.

l. In a, lifter roof tank comprising a shell and a movable roofthereover having a downwardly extending skirt attached thereto andlocated beyond the shell, stabilizing and guide means com prising aplurality of inclined roller guides attached to the outside of theshell, a plurality of vertical roller guides attached to the outside ofthe shell, a plurality of rollers attached to the roof skirt andengaging the vertical guides, a plurality of rollers engaging theinclined guides and attached to a common horizontal structural member ofannular shape extending around the shell but spaced therefrom, and armsof equal length connected at one end to the roof skirt and connected atthe other end to the structural member, each of said arms being movablein a plane substantially parallel to the shell wall.

DONALD E. LARSON (No references cited)

